Gilbert said Monday that he hasn't landed a tenant for the 176,000 square-foot building but believes it's ideal for one occupant. The original building was constructed in 1927 and an eight-story annex was added in 1951.

The purchase price wasn't disclosed for the building, which has been vacant since 2004.

In the past year, Gilbert's Rock Ventures LLC has bought nine buildings, three parking structures and one lot with an aim to create an entrepreneurially focused, technology district.

The Cleveland Cavaliers owner made the announcement from the M@dison Building, a five-story structure Rock Ventures bought and spent $12 million renovating. Other holdings include the Chase Tower and First National Building.

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